Note: this reflects the state of the demo on 2018-01-22. If you want to check out code that behaves the way this document describes, I suggest checking out the commit where this doc was last modified.
The Icestick is a low-cost evaluation board for the ICE40 HX1K FPGA. (At the time of this writing it's about US$11.)
The CFM Icestick demo boots to a minimal Forth environment with a serial console. The full compiler and assembler are available, but mass storage support is not, due to RAM constraints -- a smidge over 2 kiB is left for your use after loading bsforth.
To build, you will need recent (as of late 2017) versions of
All further commands should be run from the cfm checkout.
First, invoke Stack to set up an isolated environment with the right version of GHC and dependencies:
$ stack setup
$ stack build
(The makefile does that, but it hides the output -- if something fails it's much easier to see with the commands above.)
Plug in your Icestick and run
$ make -j program-icestick
This should run synthesis, bootstrap the Forth environment, and flash the bitstream onto the Icestick.
BsForth's console is on the Icestick's USB-to-UART interface (which typically
enumerates as /dev/ttyUSB1 on Linux). The settings are:
- 115200 bps
- Hardware (RTS/CTS) flow control on
System reset is connected to DTR, so your terminal must assert DTR for the system to start. (In Minicom, set the DTR drop time under Modem and Dialing, and you can use the Hangup command to reset the demo system.)
The system returns its internal reset system on DCD.
To verify that it's working, run words or 0 ledtog.